Party featuring frat boys in wifebeaters, thrown in brotherly comradery with southern country boys who represent all-american ideals of rugged individualism and brotherhood. Wifebeater parties are great opportunities to show off one's toned muscles, manly musk, and fully re-grown armpit hair (shaved at initiation), especially to the ladies and fraternity brothers.
I think the TV show "COPS" had a lot do with the creation of this word. Every time they showed a guy getting arrested for beating his wife he was wearing one of those sleeveless undershirts.
A guy that thinks he's tougher than you because he wears a wife beater even though they were only cool for a week or two back in 1996. This is usually accompanied by a series of unoriginal tatoos that can be found on any kid that dropped out of high school between the years 1992-1997